<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>flip</title>
</head>

<body>
    <div>打开浏览器控制台查看结果</div>
    <script>
        const flip =
            handler =>
                (first, ...rest) =>
                    handler(...rest, first);
        let a = { name: 'John Smith' };
        let b = {};
        const mergeFrom = flip(Object.assign);
        let mergePerson = mergeFrom.bind(null, a);
        console.log(mergePerson(b));; // == b
        b = {};
        console.log(Object.assign(b, a));; // == b
    </script>
</body>

</html>